The treatment or prevention of bed sores (i.e. pressure ulcers or decubitus ulcers) is an ongoing field of study. Special mattresses or mattress overlays have been used to reduce or prevent the development of these ulcers. They typically form on patients who are bedridden and unable to move or move frequently from one position to the next. The pressure ulcer can be defined as localised damage to the skin and/or underlying tissues usually situated on a bony prominence and deriving from pressure or pressure combined with the force of friction.
Multiple products have been developed to treat this disorder. These include mattresses/overlays formed from standard foam, compound foam, gel, fibre, air, water, spheres, and natural fleece, and alternating pressure mattresses/overlays, fluidised beds, and air-release beds. Other support surfaces can be used like bed rotation, re-positioning of operative surfaces, pillows, and protection for bony prominences. Two notable products in this area are the Akton® viscoelastic mattress overlay and the Aiartex® mattress overlay.
The Akton® viscoelastic mattress overlay is about 15.9 mm thick and is one of the most widely used pressure relieving device for the prevention of pressure ulcers, especially in the United States. The mattress overlay is made of 100% Akton viscoelastic polymer which is a vulcanized cross-linked rubber material with the ability to maintain its shape, stretch, deflect an applied load and absorb shock. The mattress overlay weights 35 kg.
The Aiartex® mattress overlay is a CE-marked class 1 medical device currently used in the treatment and prevention of pressure ulcers and is a macro-porous three-dimensional material (9 mm thick) entirely made in flame retardant polyester. FIG. 1 illustrates an example of Aiartex® 100 which consists of two parallel and superimposed layers (upper layer 102 and lower layer 104) connected by transversal suspensory monofilaments 106. It is highly porous (with pores 110 larger than one millimeter on the upper layer 102) and elastic, with complete return to its original shape after decompression. Small, interconnected air spaces 108 are formed between the upper and lower layers 102, 104 by the spacing of the monofilaments 106, which provide continuous ventilation of the skin while improving load distribution with a reduction of pressure peaks. The upper layer 102 is soft, made of multi-filament, and drains any exudates and conveys them to the lower layer 104 by capillarity and gravity through the transversal monofilaments 106. This action keeps the skin dry and aerated which prevents maceration. The intermediate transversal layer 106 and the lower layer 104 are both made of monofilament. The mattress overlay 100 weighs approximately 800 g and can weigh 850 g.
While it is known that mattress overlays can prevent bedsores there is little research to see if they can prevent any other ailments, including back pain. It is known that certain mattresses or support pillows can aid with both bed sores and muscle pain (see, U.S. Pat. Nos. 8,166,589 and 6,966,088) but either they are complete mattresses which are complex and expensive or partial solutions which do not allow the user to change position. What is needed is a simple mattress overlay to allow a user to adapt an existing mattress and also allow a full range of movement.